<template>
<button @click="isShow=!isShow">显示/隐藏</button>
<Demo v-if="isShow"/>
</template>

<script>
import Demo  from './components/HelloWorld.vue'

import { ref } from 'vue'; 
export default {
  name: 'App',
  components:{Demo},
  setup(){
    let isShow = ref(true);
    return{isShow}
  }
}
</script>
